Leaching experiments with highly radioactive French glasses at Studsvik

Glasses with incorporated highly active radioactive waste is now leached at Studsvik with solutions approximating subsurface water from crystalline rocks. Results at embient temperature give leach rates somewhat higher than the values obtained by the French, but the values are still incomplete. For Pu, the values obtained are about 4 x 10-7 g cm-2 day-1 which is somewhat higher than the French values of approximately 2 x 10-7 g cm-2 day-1. The temperature factor seems to be approximately 10 for Sr and Cs and very small for Pu. The active glasses contain approximately 20 % waste oxides compared to 9 % contracted for waste from Swedish reactors